Uses the Cloud Data Loss Prevention API to re-identify sensitive data in a string that was encrypted by format-preserving encryption (FPE) with a surrogate type. The encryption is performed with an unwrapped key.
def reidentify_free_text_with_fpe_using_surrogate(
project,
input_str,
alphabet="NUMERIC",
surrogate_type="PHONE_TOKEN",
unwrapped_key="YWJjZGVmZ2hpamtsbW5vcA==",
):
"""Uses the Data Loss Prevention API to reidentify sensitive data in a
string that was encrypted by Format Preserving Encryption (FPE) with
surrogate type. The encryption is performed with an unwrapped key.
Args:
project: The Google Cloud project id to use as a parent resource.
input_str: The string to deidentify (will be treated as text).
alphabet: The set of characters to replace sensitive ones with. For
more information, see https://cloud.google.com/dlp/docs/reference/
rest/v2beta2/organizations.deidentifyTemplates#ffxcommonnativealphabet
surrogate_type: The name of the surrogate custom info type to used
during the encryption process.
unwrapped_key: The base64-encoded AES-256 key to use.
Returns:
None; the response from the API is printed to the terminal.
"""
# Import the client library
import google.cloud.dlp
# Instantiate a client
dlp = google.cloud.dlp_v2.DlpServiceClient()
# Convert the project id into a full resource id.
parent = f"projects/{project}"
# The unwrapped key is base64-encoded, but the library expects a binary
# string, so decode it here.
import base64
unwrapped_key = base64.b64decode(unwrapped_key)
# Construct Deidentify Config
transformation = {
"primitive_transformation": {
"crypto_replace_ffx_fpe_config": {
"crypto_key": {"unwrapped": {"key": unwrapped_key}},
"common_alphabet": alphabet,
"surrogate_info_type": {"name": surrogate_type},
}
}
}
reidentify_config = {
"info_type_transformations": {"transformations": [transformation]}
}
inspect_config = {
"custom_info_types": [
{"info_type": {"name": surrogate_type}, "surrogate_type": {}}
]
}
# Convert string to item
item = {"value": input_str}
# Call the API
response = dlp.reidentify_content(
request={
"parent": parent,
"reidentify_config": reidentify_config,
"inspect_config": inspect_config,
"item": item,
}
)
# Print results
print(response.item.value)
